This invention relates to apparatus for the batch-wise coating of substrates under a vacuum having a vacuum chamber with a coating system and a plurality of lock chambers with substrate holders which can be introduced into the vacuum chamber.
In the batch-wise operation of discontinuously functioning vacuum coating apparatus, a certain amount of time is always lost in the passage of the batches through lock chambers, since the vacuum chamber cannot be used for coating during that time. This is of secondary importance as long as the coating procedure takes several times longer than the charging operation. As the output of vacuum coating apparatus, such as electron beam evaporators, for example, increases, the time required for the coating procedure can be considerably reduced, so that it becomes increasingly desirable to reduce the time required for the loading of the apparatus. The delay involved in this operation becomes more disadvantageous when the coating process is preceded by a time-consuming preliminary treatment, such as, for example, a glow discharge treatment for purification purposes or a heating of the substrates, if these operations are not performed in the vacuum chamber itself.